JP3156584B2 - Induction heating cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction heating cooker for heating food in a container to be heated by using an induction heating type heating means.

[0002]

2. Description of the Related Art In recent years, electromagnetic cookers have begun to spread in place of gas stoves as commonly used induction heating cookers, and their characteristics of cleanliness, comfort and safety have been evaluated. . It is also characterized by being easy to control because of its electrical configuration.

Hereinafter, a conventional induction heating cooker of the induction heating system will be described with reference to FIG. FIG. 12 is a schematic view of a conventional induction heating cooker. Reference numeral 101 denotes an inverter (heating means), which includes a heating coil 102, a resonance capacitor 1
03, a transistor 104, a diode 105, and a control circuit 106 constitute a main circuit. 107 is a container to be heated, and 108 is a plate. The heated container 107 is placed on the plate 108, and an alternating magnetic field generated by a high-frequency current flowing through the heating coil 102 is linked to the heated container 107 to perform induction heating. 109 is the container to be heated 10
7 is a temperature sensor for detecting the temperature of the container 7 to be heated.
The temperature at the approximate center of 7 is detected via the plate 108. Reference numeral 110 denotes a setting key for setting the output of the inverter 101. The setting key 110 includes a run / stop key 110-a for instructing start / stop of heating and an up key 110-b for setting the output of the inverter 101 higher by one step. . It comprises a down key 110-c for setting the output of the inverter 101 low for each step. Reference numeral 111 denotes a microcomputer (arithmetic processing unit) that controls the inverter 101 according to the outputs of the temperature sensor 109 and the setting key 110.

The operation of the induction cooking device configured as described above will be described. Run / Stop key 110-a
When the heating is started / stopped by pressing, the microcomputer 111 outputs an operation / stop signal to the control circuit 106,
Oscillating / stopping inverter 101 to start induction heating /
Stop. Next, when the heating output is set high / low by pressing the up key 110-b or the down key 110-c, the microcomputer 111 outputs a control signal to the control circuit 106 and changes the oscillation waveform of the inverter 101 to change the heating output. Change.

When the temperature of the container 107 to be heated detected by the temperature sensor 109 during the normal operation as described above exceeds a set value set in the microcomputer 111, the microcomputer 111 sets the temperature. Key 1
A stop signal is output to the control circuit 106 regardless of the set value of 10, and the inverter 101 is stopped. Thereafter, when the temperature of the container to be heated 107 becomes lower than the set value, the inverter 107 is operated again with the original set output. The above operation is repeated to change the temperature of the heated container 107 around the set temperature. If the container 107 to be heated is left at a high temperature, this operation is continued.
By stopping the inverter 101 unconditionally after a predetermined time from the first stop of the heating,
We offer products that take safety into consideration when left at high temperatures.

[0006]

However, in such a conventional induction heating cooker, if the temperature of the container to be heated at least once exceeds the set temperature, the inverter always stops after a predetermined time. Therefore, in cooking with extremely light load such as sprouts, which have almost the same temperature transition as when the heated container is left at high temperatures, the inverter stops during cooking, and the temperature of the heated container decreases, resulting in reduced cooking performance. I was letting it.

The present invention has been made to solve the above-mentioned problems, and the inverter is stopped at an early stage when the container to be heated is left at a high temperature to maintain safety. It is an object of the present invention to provide an induction heating cooker in which an algorithm for performing a predetermined operation by easily distinguishing a distinction from the arithmetic processing means is provided.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a heating means for performing cooking, a plate on which a heated container is placed, and a temperature for detecting the temperature of the heated container. A sensor, output detection means for detecting the magnitude of the output of the heating means, input means for setting the output of the heating means, and the heating in accordance with the outputs of the temperature sensor, the input means and the output detection means. A first processing unit configured to detect a use state of the heated container in accordance with at least output values of the temperature sensor, the output detection unit, and the input unit. Built-in detection algorithm. By using this means, once the temperature of the container to be heated rises and exceeds the temperature set value, the arithmetic processing means determines that the container to be heated may be left at a high temperature, and the output detection means,
It is to determine whether the container to be heated is left at high temperature or during cooking based on the output values from the temperature sensor and the input means.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to solve the above-mentioned problems, the present invention is provided with an arithmetic processing means for shifting to a first detection algorithm when the temperature of a container to be heated reaches a predetermined temperature or higher.

With this arrangement, when the temperature of the container to be heated becomes equal to or higher than the predetermined temperature, the container to be heated is left at a high temperature or extremely light in load based on the output values from the output detecting means, the temperature sensor and the input means. It is possible to determine whether cooking is being performed (the heat capacity itself of the food such as fried sprouts is small), and if the container to be heated is left at a high temperature, the heating means can be stopped early.

The arithmetic processing means compares the reference value stored before and after the first detection algorithm with the average value after the first detection algorithm, and adjusts the output of the heating means according to the magnitude of the comparison. .

Thus, the comparison with the average value is performed in detail according to the value of the reference value which changes depending on the type, shape, size, etc. of the container to be heated.

The arithmetic processing means may determine that the average value is the maximum value of 5
When it is determined that it is 0% or less, the output of the heating means is adjusted.

Thus, the average value during cooking is approximately 70% of the maximum value, and the average value when left at high temperature is approximately 40%. Can be determined as the simplest 50% (the maximum value is divided by 2) to continue or stop heating.

The arithmetic processing means changes the reference value to a set value corresponding to the output of the input means when the output of the heating means is changed from the input means to an output having a setting lower than the reference value.

As a result, the output is suppressed during the execution of the first detection algorithm, and the average value is reduced. However, by setting the reference value to the set value, the correlation with the average value can be made, and the determination can be made reliably. .

When the output of the heating means is changed from the input means during execution of the first detection algorithm, the arithmetic processing means changes the reference value and the average value to predetermined values, and again executes the first detection algorithm.
The detection algorithm is started.

Thus, when the input setting is changed, the reference value and the average value are re-calculated to perform the correction, so that the determination can be made reliably.

The arithmetic processing means has a built-in second detection algorithm for automatically interrupting the output of the heating means temporarily when the container to be heated is not properly placed on the plate. Is executed, when the second algorithm is executed during execution of the first detection algorithm, the first detection algorithm is forcibly terminated.

Thus, it can be determined that the container to be heated has not been left, and the determination can be made earlier than when the predetermined time for obtaining the average value has elapsed. Further, since the output of the heating means is small during the execution of the second algorithm, the average value becomes small, and it is possible to prevent erroneous detection of stopping the heating by reliably determining that the container to be heated is left at high temperature.

[0021]

【Example】

(Embodiment 1) FIGS. 1 to 3 are a schematic diagram and a flowchart showing a first embodiment of the present invention. In FIG. 1, 1 is an inverter for cooking, 9 is an inverter power supply, 2 is a container to be heated, 3 is a plate, 4 is a temperature sensor for detecting the temperature of the container 2 to be heated, and 5 is an input of the inverter circuit 1. A current detector for detecting a current value, 6 is a setting key for setting an output of the inverter circuit 1, 7 is a temperature sensor 4, a setting key 6, and a microcomputer for controlling the inverter circuit 1 according to the output of the current detector. are doing. The inverter 1 includes a main circuit including a heating coil 1-a, a transistor 1-b, a resonance capacitor 1-c, a diode 1-d, and a control circuit 1-controlling the transistor 1-b.
f. The setting key 6 includes a heating / running start / stop key 6-a, an output (heat) up key 6-b, and an output (heat) down key 6-c. The up key 6-b and the down key 6-c change the output of the inverter 1 stepwise each time the key is pressed, and change the set value to be compared with the current detector 5 stepwise. . Each time the up key 6-a is pressed, the set value increases, and the output of the inverter 1 increases. Conversely, each time the down key 6-b is pressed, the set value decreases, and the output of the inverter 1 decreases. In this embodiment, the set value is 131.
W, 230W, 370W, 480W, 900W, 145
It changes in seven stages of 0W and 2000W.

The microcomputer 7 stores therein an algorithm shown in FIG. Next, the operation of the induction heating cooker will be described with reference to the flowchart shown in FIG. Step 1 detects whether the run / stop key 6-a has been pressed. When the run / stop key 6-a is pressed, one of the seven set values is selected. In the present embodiment, first, 145
Select 0W. Steps 2 and 3 detect whether the up key 6-b and the down key 6-c have been pressed, and change the output set value read in step 1 one step at a time. In step 4, the temperature of the container 2 to be heated input from the temperature sensor 4 is compared with a temperature reference value set in five stages. Step 5 if the minimum temperature reference is higher
And the output to the inverter 1 is decreased by one step each time the temperature of the container 2 to be heated exceeds the temperature set value set in five steps. When the temperature exceeds the maximum temperature set value, the output of the inverter is stopped. The process proceeds to the first detection algorithm. Step 5 is to bring the output of the inverter 1 closer to a constant, and compare the output of the current detector with the output set value. If the output of the current detector is large, a control signal is output to the control circuit 1-f to limit the output of the inverter 1. The above steps are repeated to heat the container 2 to be heated while detecting the set output of the inverter 1 and the temperature.

Next, FIG. 3 shows the first detection algorithm.
This will be described with reference to the flowchart shown in FIG. In the present embodiment, the first detection algorithm determines whether the heated container 2 is left at a high temperature or is cooking after 512 seconds. First, in step 1, timer measurement is started. Step 2 to Step 4
The process proceeds to step 5 while the output information of the temperature sensor 4, the setting key 6 and the current detector 5 is stored until
When the timer reaches 512 seconds, the output information is processed in step 6 to generate a judgment value. In step 7, the judgment value is compared with the judgment criterion to determine whether or not the heated container 2 is left at a high temperature.

In this way, the first detection algorithm operates and determines whether the heated container 2 is left at a high temperature or is cooking during 512 seconds, so that the output of the inverter is adjusted at an early stage, and the safety is improved. Improves sex and cooking performance.

The processing 1 to processing 3 are performed by the inverter 1
, Restarting the timer to the initial value, returning the storage of each output information to the initial value, and the like.

(Embodiment 2) FIGS. 1 and 4 to 6 are a schematic diagram, a flowchart, and a time transition diagram of a temperature sensor 4 and a current detector 5 showing a second embodiment of the present invention. Second
The schematic diagram of this embodiment is the same as that of FIG. 1 and the description is omitted. The microcomputer 7 internally stores the algorithms shown in FIGS. 4 and 5, and the operation thereof will be described below. First, the algorithm during the normal operation will be described with reference to the flowchart shown in FIG. Basically, it is the same as that of the first embodiment shown in FIG. 2, but the output of the inverter 1 differs in the current value of the current detector 5 depending on the shape and material of the container 2 to be heated. During normal operation, the maximum value of the current is stored in the processing from step 6 to step 8 and used as a reference value. This is a criterion for a first detection algorithm described later.

FIG. 5 shows the first detection algorithm.
This will be described with reference to the flowchart shown in FIG. First, in step 1, timer measurement is started. In step 2, heated vessel 2
When the temperature becomes equal to or lower than the predetermined value, the inverter 1 operates in step 3 and a current corresponding to the set output flows through the current detector 5. Here, the temperature of the container 2 to be heated is close to the set temperature,
It changes like In step 4, the current value within a predetermined time is added and stored in variable 2. Then, when the timer reaches 512 seconds in step 5, the process proceeds to step 6, and the average current value during execution of the first detection algorithm is calculated. Then, in step 7, the reference value and the average value are compared. If the container 2 to be heated is left at a high temperature, even if the inverter operates, the temperature immediately rises due to the small heat capacity, and the temperature amplitude occurring in FIG. 6 is small. As a result, the time during which the inverter 1 is outputting becomes shorter, and the average value becomes smaller. However, during cooking, since the heat capacity is large, the temperature amplitude is relatively large and the output time of the inverter 1 is long, and the average value is large. From the above, when the reference value and the average value stored during the normal operation are compared, the average value is smaller than the reference value when the heated container 2 is left at high temperature, and larger than the reference value during cooking. Therefore, both can be distinguished.

The reason why the maximum value is used as a criterion for determination is that the maximum value before the first detection algorithm is shifted to when the heated container 2 is left at a high temperature if the shape and material of the heated container 2 do not change. This is because it is proportional to the experimental data during cooking.

(Embodiment 3) FIGS. 1, 4 and 7 are a schematic diagram and an algorithm showing a third embodiment of the present invention. The schematic diagram of the third embodiment is similar to that of FIG. 1, and the description is omitted. The microcomputer 7 internally stores the algorithms shown in FIGS. 4 and 7, but the algorithm of FIG. 4 has been described in the second embodiment and will not be described. Hereinafter, the operation of the algorithm of FIG. 7 will be described.

FIG. 7 is a flowchart of the first detection algorithm, and its operation will be described below. First, in step 1, timer measurement is started. In step 2, heated vessel 2
When the temperature becomes equal to or lower than a predetermined value, the inverter 1 operates in step 3 so that the output set value has already been set.
A current flows through the current detector 5. In step 4, the current value within a predetermined time is added and stored in variable 2. Then, when it reaches 512 seconds in step 5, the process proceeds to step 6, and the average current value during execution of the first detection algorithm is calculated. Then, in step 7, the reference value and the average value are compared. If the container to be heated 2 is left at a high temperature, even if the inverter operates, the temperature immediately rises because the heat capacity is small, and the output time of the inverter 1 is short, so that the average value is small. According to the experimental data, it is found that when the average value is obtained using all kinds of heated containers, the average value is 40% or less of the reference value.

However, during cooking, the heat capacity is large,
Since the temperature does not rise quickly, the output time of the inverter 1 is long, and the average value becomes large. According to the experimental data, it is known that the average value is 70% or more of the reference value when the average value is obtained using all kinds of heated containers.
From the above, when the average value is compared with 50% of the reference value as the criterion, it is possible to determine whether the heated container 2 is left at high temperature or during cooking.

The criterion for determination is 40 to 70% of the reference value.
Although any number may be used, especially when 50% is used,
This is because the internal operation of the microcomputer 7 is conveniently performed. That is, the reference value is only divided by 2 ^1, in which perform earliest process.

(Embodiment 4) FIGS. 1, 7 and 8 are a schematic diagram and an algorithm showing a fourth embodiment of the present invention. The schematic diagram of the fourth embodiment is the same as that of FIG. 1 and the description is omitted. The microcomputer 7 internally stores the algorithms shown in FIGS. 7 and 8, but the algorithm of FIG. 7 has been described in the third embodiment and will not be described. Hereinafter, the operation will be described with reference to FIG.

FIG. 8 is a flowchart at the time of normal operation, and the operation will be described below. Step 1 detects whether the run / stop key 6-a has been pressed. When the run / stop key 6-a is pressed, one of the seven set values is selected. In this embodiment, 1450 W is selected first. Steps 2 and 3 detect whether the up key 6-b and the down key 6-c have been pressed, and change the output set value read in step 1 one step at a time. In step 4, the temperature of the container 2 to be heated input from the temperature sensor 4 is compared with a temperature reference value set in five stages. If the minimum temperature reference value is higher, the process proceeds to step 5, and the output to the inverter 1 is reduced by one step each time the temperature of the container 2 to be heated exceeds the temperature set value set in five steps. If the value is exceeded, the output of the inverter is stopped and the process shifts to the first detection algorithm.

Step 5 is to bring the output of the inverter 1 closer to a constant, and compare the output of the current detector with the output set value. If the output of the current detector is large, the control circuit 1
−f to output a control signal to limit the output of the inverter 1. In step 6, the maximum value of the current is stored, and in step 7, it is determined whether the reference value is the maximum value or the set value. This determination is made for the following reason. For example, when the output of the inverter 1 is changed from 1450 W to 480 W by the down key 6-c in step 3, the average current value obtained during execution of the first detection algorithm is 48 at the maximum.
It does not exceed 0W. Therefore, the average current (the maximum value of 480 W) is always smaller than 50% of the reference value (1450 W), and it is erroneously determined that the heated container 2 is left at a high temperature, and the heating is stopped. In order to prevent the above, when the set value becomes equal to or less than the maximum value, the reference value is set to the set value to obtain a correlation with the average value. The reference value obtained by repeating the above operation is used in the first detection algorithm.

When the set value is smaller than the maximum value, the reference value is changed to the set value, but the maximum value updated so far is held. Accordingly, when the output of the inverter is limited by the temperature or when the original output setting is changed by the up key during execution of the first detection algorithm, the maximum value is newly set as the reference value, and thereafter, the output of the current detector is output. The reference value can be obtained without reading the data, and other processing can be performed quickly.

(Embodiment 5) FIGS. 1, 4 and 9 are a schematic diagram and an algorithm showing a fifth embodiment of the present invention. The schematic diagram of the fifth embodiment is the same as that of FIG. 1 and the description is omitted. The microcomputer 7 internally stores the algorithms shown in FIGS. 4 and 9, but the algorithm of FIG. 4 has been described in the second embodiment and will not be described.

The operation will now be described with reference to FIG.
FIG. 9 is a flowchart of the first detection algorithm, and its operation will be described below. First, in step 1, timer measurement is started. When the temperature of the container 2 to be heated becomes equal to or lower than the predetermined value in step 2, the inverter 1 operates in step 3 and a current corresponding to the setting key 6 flows through the current detector 5. In step 4, the current value within a predetermined time is stored as a variable 2. Step 6 detects whether the up key 6-b has been pressed. Up key 6-b or Down key 6
If -c is pressed, the variable 2, the reference value, and the count value of the timer are returned to 0, and the process returns to step 1. When the timer counts 512 seconds in step 5, the process proceeds to step 7 and compares the maximum value with the average value. If the average value is 50% or less of the reference value, it is determined that the heated container 2 is left at a high temperature, and the heating is stopped. The average value is 5 of the reference value
If it is 0% or more, it is determined that cooking is in progress, and the operation returns to the normal operation.

As described above, during execution of the first detection algorithm, if the current value is limited by pressing the setting key, the correlation between the reference value and the average value is lost, so the reference value and the average value are calculated again. Things.

(Embodiment 6) FIGS. 1, 4, 10 and 11
FIG. 9 is a schematic diagram and an algorithm showing a sixth embodiment of the present invention. The schematic diagram of the sixth embodiment is similar to that of FIG. 1, and the basic operation is as described in the first embodiment. In the sixth embodiment, a voltage detector 8 is further configured. The voltage detector 8 is provided to protect the transistor 1-b against withstand voltage, and outputs a signal to the microcomputer 7 when the voltage exceeds a predetermined voltage. The microcomputer 7 internally stores an algorithm shown in FIG.

FIG. 10 is a normal flowchart of the sixth embodiment, and its operation will be described below. Step 1
Detects whether the run / stop key 6-a has been pressed. When the run / stop key 6-a is pressed, the output set value 1 set to the initial value in the microcomputer 7 and the temperature reference value are read. Steps 2 and 3 detect whether the up key 6- and down key 6-c have been pressed, and change the output set value read in step 1.
The second detection algorithm detects the load state of the container 2 to be heated. Based on the outputs of the current detector 5 and the voltage detector 8 in FIG. 1, the value is appropriate for a normal load, but for a light load, despite the small output of the current detector 4,
The output of the voltage detector 8 is large. The second detection algorithm makes this determination and stops the inverter so that the transistor 1-f does not cause voltage breakdown.

Step 4 compares the temperature of the heated container 2 input from the temperature sensor 4 with a temperature reference value. If the temperature reference value is higher, the process proceeds to step 5, and the heated container 2
When the temperature is high, the operation shifts to the first detection algorithm. Step 5 is to bring the output of the inverter 1 closer to a constant, and compare the output of the current detector with the output set value. If the output of the current detector is large, a stop signal is output to the control circuit 1-f to stop heating. If the set value is larger, an operation signal is output to the control circuit 1-f to start heating. The above steps are repeated to heat the container 2 to be heated.

Next, FIG. 1 shows the first detection algorithm.
1 will be described. First, in step 1, timer measurement is started. When the temperature of the container to be heated 2 becomes equal to or lower than the predetermined value in step 2, the inverter 1 operates in step 3 and a current flows so that the output set to the current detector 5 is obtained. In step 4, the current value within a predetermined time is added and stored in variable 2. Next, the load state of the heated container 2 similar to the second detection algorithm is determined. If the load is light, the reference value and the average value are returned to the initial values after the inverter 1 is stopped, and the operation returns to the normal operation. And step 5
When the time reaches 512 seconds, the process proceeds to step 6, and the average current value during execution of the first detection algorithm is calculated. In step 7, the reference value calculated before the execution of the first detection algorithm is compared with the average value. If the container 2 to be heated is left at a high temperature, even if the inverter operates, the temperature immediately rises due to the small heat capacity, and the temperature amplitude occurring in FIG. 6 is small. As a result, the average value is small. However, since the heat capacity is large during cooking, the temperature amplitude is relatively large and the average value is large. From the above, when the average value is compared with the maximum value stored during the normal operation as a criterion, it is possible to determine whether the heated container 2 is left at high temperature or during cooking.

Note that the reference value is used as a criterion for determination.
If the shape and material of the heated container 2 do not change, the first
The reason is that the reference value before the shift to the detection algorithm is proportional to the experimental data when the heated container 2 is left at a high temperature and during cooking.

[0045]

As described above, according to the first aspect of the present invention, when the temperature of the container to be heated becomes high, the process proceeds to the first detection algorithm, and it is determined whether the container to be heated is left at a high temperature during cooking. Since it is determined whether or not there is, and the inverter is appropriately controlled, there is no erroneous detection that heating stops during cooking, and the cooking performance can be improved. In addition, since the automatic monitoring for overheating of the container to be heated is performed, safety can be improved.

According to the second aspect of the present invention, the criterion for determining whether or not the container to be heated is left at a high temperature is the first criterion.
Is a reference value obtained before the process shifts to the detection algorithm, and its size changes according to the material and shape of the container to be heated, the cooking state, and the size of the output set value by the input key. Therefore, it is not necessary to set detailed criteria for each material / shape of the container to be heated, the cooking state, and the output set value, so that the contents stored in the microcomputer can be simplified, and the cost can be reduced by downsizing the microcomputer and reducing the capacity. can do.

According to the third aspect of the present invention, the determination criterion is set to 50% of the reference value, so that cooking is being performed (about 70% of the reference value) and the container to be heated is left at a high temperature (reference value). (Less than 50% of the value). If the cooking is being performed, the average value of the input current is returned to the initial value and the heating is continued, so that the cooking performance such as stopping the heating during the cooking is not reduced.

According to the fourth aspect of the present invention, the first
When the set output is changed to a small value by the input key during the execution of the detection algorithm, the reference value is changed to the set value when the reference value is smaller than the maximum value. Thus, the average value and the reference value are corrected. Therefore, it is possible to avoid a decrease in cooking performance such as stopping heating during cooking. Further, since it is not necessary to fix the reference value to the set value and re-measure the maximum value, the flow of the algorithm can be simplified, and higher-speed processing can be performed as a microcomputer.

According to the fifth aspect of the present invention, when the setting output is changed, the stored variable 2 and the reference value are set to 0.
, And the measurement is performed again, so that the determination can be reliably performed, and the cooking performance such as the stop of the heating of the inverter during cooking does not decrease.

Further, according to the present invention, it is determined that there is a user in the vicinity when the user operates the container to be heated, when the operation shifts to the second detection algorithm. it can. Therefore, security can be maintained even if the first detection algorithm is terminated, and other algorithms can be executed with good responsiveness. During the execution of the second algorithm, the heating value is small, so the average value is small. By comparing this value with the reference value, it is possible to reliably determine that the apparatus has been left at a high temperature and to prevent erroneous detection of stopping heating.

[Brief description of the drawings]

FIG. 1 is a schematic view of an induction heating cooker according to a first embodiment of the present invention.

FIG. 2 is a flowchart at the time of a normal operation of the induction heating cooker;

FIG. 3 is a flowchart of a first detection algorithm of the induction heating cooker.

FIG. 4 is a flowchart showing a second embodiment of the present invention during normal operation of the induction heating cooker;

FIG. 5 is a flowchart of a first detection algorithm of the induction cooking device.

FIG. 6 is a time transition diagram of the temperature and the current value of the heated container of the induction heating cooker.

FIG. 7 is a flowchart of a first detection algorithm of the induction heating cooker according to the third embodiment of the present invention.

FIG. 8 is a flowchart at the time of a normal operation of the induction heating cooker according to the fourth embodiment of the present invention.

FIG. 9 is a flowchart of a first detection algorithm of the induction heating cooker according to the fifth embodiment of the present invention.

FIG. 10 is a flowchart illustrating a sixth embodiment of the present invention during normal operation of the induction heating cooker;

FIG. 11 is a flowchart of a first detection algorithm of the induction heating cooker according to the sixth embodiment of the present invention.

FIG. 12 is a schematic diagram of an induction heating cooker showing a conventional example.

[Description of Signs] 1 heating means (inverter) 2 container to be heated 3 plate 4 temperature sensor 5 output detection means (current detector) 6 input means (setting key) 7 arithmetic processing means (microcomputer)

──────────────────────────────────────────────────の Continued on the front page (72) Inventor Hirofumi Noma 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Yuji Fujii 1006 Kazuma Kadoma, Osaka Pref.Matsushita Electric Industrial Co., Ltd. JP-A-5-258852 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05B 6/12

Claims (6)

(57) [Claims] 1. A heating means for performing heating and cooking, a plate on which a container to be heated is placed, a temperature sensor for detecting a temperature of the container to be heated, and an output for detecting a magnitude of an output of the heating means. Detecting means, input means for setting an output of the heating means, and arithmetic processing means for controlling the heating means in accordance with outputs of the temperature sensor, the input means and the output detecting means, wherein the arithmetic processing means Has a first detection algorithm for detecting a use state of the container to be heated in accordance with at least the output values of the temperature sensor, the output detection unit, and the input unit, and the container to be heated is a predetermined temperature or higher. , The process proceeds to the first detection algorithm, and determines whether the container to be heated is left at a high temperature or cooking. 2. The arithmetic processing means uses the maximum value of the output obtained by the output detection means as a reference value before shifting to the first detection algorithm, and within a predetermined time after shifting to the first detection algorithm. The induction heating cooker according to claim 1, wherein the average value of the output obtained in (1) is stored, and the output of the heating means is adjusted when the average value and the reference value satisfy a predetermined condition. 3. The arithmetic processing means adjusts the output of the heating means when the average value of the output obtained by the output detection means within a predetermined time after the shift to the first detection algorithm is 50% or less of the reference value. The induction heating cooker according to claim 2, wherein 4. The arithmetic processing means, when the output of the heating means is changed to a setting lower than the maximum value by the input means,
4. The induction heating cooker according to claim 2, wherein a reference value is changed to a set value corresponding to an output of the input means. 5. The arithmetic processing means, when the output of the heating means is changed by the input means during execution of the first detection algorithm, changes the reference value and changes the average value during processing to a predetermined value, The induction heating cooker according to claim 2 or 3, wherein the first detection algorithm is started again. 6. The arithmetic processing means has a second detection algorithm for temporarily interrupting the output of the heating means when the container to be heated is not properly placed on the plate, and the first detection algorithm. The induction heating cooker according to claim 2 or 3, wherein the first detection algorithm is forcibly terminated when the second algorithm is executed during the execution of (1).